1. Field
The invention is in the field of vacuum cleaners that operate on compressed air.
2. State of the Art
Vacuum cleaners that operate on compressed air are known, see for example U.S. Pat. Nos. 2,863,525 and 5,142,730. Such vacuum cleaners operate from a source of compressed air such as available in many factories and garages. Electrical connection is unnecessary and the risk of electrical sparking eliminated. Further, such vacuum cleaners can produce high air flow and, as opposed to most electrical vacuums, the vacuum produced is increased as the flow of air into the vacuum is reduced. Such vacuums have been found particularly useful in industrial applications for liquid spill pickup. The inventor has found that such vacuums are particularly useful in automobile repair stations and shops where spills of oil, transmission fluid, antifreeze, gasoline, water, etc. occur during auto and truck repair.
The compressed air vacuum cleaner of the parent application, now patent No., is designed for automobile repair station and shop use and can easily and quickly pick up large amounts of spilled liquids as well as solids. However, with the vacuum cleaner of the patent, the top has to be removed to empty the vacuum cleaner. This is inconvenient and time consuming when large spills are being cleaned up as the vacuum canister can fill up quickly.